The transfer of pesticides, which is mediated by a large number of plants, is more important. However, depending on the cumulative specific rate of pesticide residues, the transfer from the vertebrate is more effective. Analysis of a large number of vultures in 27 states of the United States found that they have an average content of 7-18 Ppm, a PCB content of 10-20 Ppm, a mercury content of 1-2 ppm, and a Dickson Fortress of 0.5-1 ppm. In contrast, in many herbivores, no significant accumulation of pesticide residues was found, such as the analysis of antelopes, deer, donkeys, goats, bears, and moose in Idahua and Washington, and found that they averaged in vivo. The accumulation amount is small, the DDD content is less than 0.001 pPm, the DD2 content is 0.001-0.04 ppm, and the DDrP content is 0.023-0.122 pPm. A large proportion of scientists are familiar with the accumulation of lipophilic persistent pesticides in the body of animals, and they are at the top of the food chain. However, the level of pesticides is greater in organisms in the middle of the food chain than in the top of the food chain. The key to the fact that a person determines the accumulation of a pesticide in any organism is its metabolic process. It has been pointed out that the continuous feeding of feeds containing fixed amounts of pesticide residues does not increase the accumulation of pesticides in animals indefinitely. In the opposite pool, after a certain period of time, the rapid measurement of pesticide residues shows the content of pesticides. One explanation for the beginning of the decline, Liu's situation is: after long-term feeding of feed containing pesticides, the defense enzymes in the animals are fully induced, these songs resist the invasion of pesticides and bring the animal body to a new dynamic balance. For example, in the past few years, the hens were fed with a feed containing 1 ppm of dieldrin, and the residual amount of D. sinensis in the egg yolk was determined. It was found that the content of the egg yolk in the egg yolk reached the maximum at 300 days. In the future, the amount of dieldrin in the egg yolk began to decrease regardless of whether or not the feed containing the dieldrin was continued. The relationship between them can be expressed by a first-order kinetic reaction equation.
Accumulation occurs whenever the amount of absorption is greater than the amount of disappearance, and is also related to factors such as age and gender. According to the cumulative concentration, the accumulation of large animals is more than that of small animals. The original is not because the size of large animals is large, but because the metabolism of the weight of each unit of large animals is more invasive, so the rate of disappearance is lower. The amount of food consumed by large animals and unit weight is far less than that of small animals, which is well known.
Kliayan, California, used to be sprayed in large quantities. After 17 years of observation, it was discovered in 1969 that a western goose punctuated suddenly. At the same time, it was discovered that 'the small fish entered the ecosystem. The mass reproduction of these fish can be said to be unprecedented. Therefore DDD is diluted in this closed ecosystem. Because the daily intake of the fish is limited, the amount of pesticide residues in the bird is greatly reduced. According to the above discussion, the following conclusions can be drawn: the pesticide is determined to be ingested and disappeared in a biological system. Thinking too is that depending on the environment, pesticides may bioaccumulate, and biological dilution may occur. For animals, its uptake rate and disappearance rate are determined by the survival competition in a certain ecosystem. The content of fat in the body of the animal, W is the most important thing to decide on the metabolism of the animal. More information: Pesticide Residues Tester http://
The amount of pesticide residues in birds